More on the 05 air line

[Ericbsc]

I have more info on the mystry air line. It is starting to make sense. It comes from the top of the t9 inversion valve mounted on the rear end. The lines out run to the emergency ports on the dd-3 chambers. At the other end at the front bulkhead which the front suspension is carried by, it has a pr-2 valve. That is where it is unhooked. Best I can tell be the schematic it goes from there to the front brake r-8 relay mounted between the front wheels. That way if you loose the service port on the back the inversion valve would switch positions at 50-60 lbs. This would allow the emergency ports to pull air from the front tank when the brake is pressed. This all makes sense to me except for the way the pr-2 is mounted. It has a built in check valve which will only allow air flow in one direction. The way it is mounted the air flow can only come from the back? This is coming from the inversion valve and emergency ports.  The t-9 back there is a spring pressure switch. I did an experiment. I charged the air system and turned off the park brake. I verified that the service brake was not engaged. I then removed the pr-2 and charged that line. At this point the system had 90-100 lbs. The emergency brake did not come on. I then slowly bled the system. At about 55-60 lbs the emergency port on the dd-3s engaged, but the park brake was not engaged. I continued to bleed to 45-50 lb at which time the park brake engaged. If all of this makes sense, then my original assumptions are all correct except for the pr-2. It will allow air flow in one direction only, which means if I leave it as I found it no air would go to the emergency port. If I turn it around, air will flow to the emer. below 60 pis but has no way to escape?  the Any other ideas please chip in!! I have thought and looked at small scribble on the schematic for a lifetime!!!

[luvrbus]

Eric, now would be a good time for you to change over to the D-2 spring brake and simplify your life, doesn't cost that much and less expense down the road.  good luck

[Dreamscape]

Hi Clifford, I agree with changing to spring brakes, I did discuss that with him, giving him my recent experience in changing over. We'll see how it works out.

Paul

[Ericbsc]

What all do you need to change for them?

[Dreamscape]

Eric,

On our Eagle 01 I changed the DD-3's with 3030 Spring brake chambers and replaced my inversion valve with a QR-C1 valve. I think you have a dual brake system, mine is a single system. I need to change my treadle valve for an E-6 and add a double check valve between the front and rear tanks, which I have just haven't done yet, have the parts though. I have a write up on the procedure in the Eagles International forum, www.eaglesinternational.net. In my project thread are some pictures and information needed to make the change over. Also you will find a schematic showing what line goes where. It really is an easy change and it's more updated to the newer style brake chamber. I was able to buy everything for less than 250 bucks.

If you have any more questions, we're here to help.

Take Care,

Paul